Objective To study the efficacy and safety of carotid artery stenting(CAS) in elderly patients with internal carotid artery stenosis and its related factors.Methods Between January 2012 and July 2014,a total of 152 patients(over 65 years of age)with carotid artery stenosis were enrolled in this study,of whom 79 patients received drug treatment (control group) and 73 patients received CAS (intervention group).The two groups were followed up for one year.The patients'' scores of mRS(the modified Rankin Scale) and NIHSS(the National Institute of Health Stroke Scale) were observed and compared in the curative effect between the two groups.By means of logistic regression were analyzed the related safety factors in CAS treatment for elderly patients over 65 with extracranial stenosis of internal carotid artery.Results Both the median mRS (P<0.01) and NIHSS(P<0.05) scores were lower in intervention group than those in control group at 3,6 and 12 months follow-up,respectively.Thirty days after CAS,there occurred transient ischemic attack (TIA) in intervention group,whose incidence was significantly lower than that in control group (P<0.05).However,there was no statistical significant difference found between the two groups in the incidence of serious adverse events including TIA,cerebral hemorrhage,cerebral infarction and death(P>0.05)at one year follow-up.And logistic regression analysis showed that the previous history of cerebral infarction,residual stenosis or combined un-interferential cerebral arterial stenosis were all independent predictors of serious adverse events including TIA,cerebral infarction,cerebral hemorrhage,re-stenosis and death (P<0.05).Conclusion CAS is a safe and effective procedure for old patients with internal carotid artery stenosis.A history of cerebral infarction,combined un-interferential cerebral arterial stenosis or residual stenosis after CAS were all risk factors,which need to be effectively controlled before CAS.